1. Field of the Invention
The present invention relates to an electronic endoscope apparatus having a solid-state image pickup device (charged coupled device (CCD)) at a distal end portion of the apparatus.
2. Description of the Related Art
In recent years, endoscopes have been widely used in medical and industrial fields. Mainstream endoscopes that have been used to date employ an image guide so that a user can look into an eyepiece to observe an inside of a patient's body cavity or an interior of a jet engine, for example. Also, endoscopes of recent years are incorporated with an image pickup apparatus to take images of the inside of a patient's body cavity or the interior of a jet engine, for example, to display endoscopic images on a display of an external monitor or the like.
A technique for using such an image pickup apparatus with an endoscope is disclosed, for example, in Japanese Patent Application Laid-Open Publication No. 2006-15078. Specifically, the reference suggests a medical apparatus in which a camera head incorporating a CCD is mounted on an eyepiece of a conventional endoscope, with operating switches being provided at the camera head to configure a grasping portion.
The conventional medical apparatus mentioned above uses a technique for acquiring an endoscopic image with a camera head mounted on an eyepiece of an endoscope, which is a conventional rigid endoscope having an image guide. The endoscope disclosed in the reference is a rigid endoscope having no bending portion at a distal end part thereof.
As is well known, some electronic endoscope apparatus have a soft insertion portion having a distal end part at which a CCD is arranged. Generally, endoscopes are provided with a bending portion at a distal end portion of an insertion portion and include an operation portion provided with a bending operation knob being arranged for subjecting the bending portion to bending operation.
As disclosed in Japanese Patent Application Laid-Open Publication No. 10-234654, for example, such an operation portion has an interior which is provided with a fixed board that has been obtained by injection molding of metal. The fixed board is disposed in the operation portion in order to rotatably hold a sprocket of the bending operation knob, and also to maintain predetermined rigidity of the operation portion and to retain electrical connection to the ground of the insertion portion and a universal code.